Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
su sach » so sach, vu sach
ky lang » ky nang, ky tang, tay lang
ky dang » ky nang, ky danh
hieu va » lieu va, hieu qua
va tinh » may tinh
tinh vi » trinh vi, tinh voi, tinh va
cua tre » cua te, cuu tre, cua triet
va coc » va cuoc, va cac, va hoc
luc va » duc va, tuc va, loc va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ((ky lang) OR (ky dang)) xa hoi. hieu va coc luc va tinh vi ((cua tre) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ky lang) OR (ky dang)) xa hoi. hieu va coc luc va tinh vi ((cua tre) OR (cua viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ky lang) OR (ky dang)) xa hoi. hieu va coc luc va tinh vi ((cua tre) or (cua viet))".
• Adding a wildcard symbol may retrieve word variants: su sach ((ky lang) OR (ky dang)) xa hoi. hieu va coc luc va tinh vi ((cua tre) or (cua viet))*.